of columbus



w. J. MONTGOMERY 1,806,860

CENTRIFUGAL FAN May 26, 1931.

Filed July 11, 1927 Fig. l

Patented May 26, 1931 UNITED STATES WILLIAM J". MONTGOMERY, OF COLUMBUS,

mousse FPATENT FFECE V OHIO, ASSIGNOR TO THE JEFFREY MANU- FACTURING COMPANY, OF COLUMBUS, OHIO, A CORPORATION OF OHIO CENTRIFU AL FAN Application filed July 11,

The present invention relates to certain new and useful improvements in centrifugal fans, of the type adapted to revolve at relatively high speed for the generation of relatively cation and illustrated in the accompanying drawings of which Fig. 1 is a side elevation of a fan of the type to which my present invention relates.

Fig. 2 is a sectional view of the fan casing illustrated in Fig. 1 taken along the. central vertical axial plane of the fan wheel.

Fig. 3 is a fragmentary sectional view on an enlarged scale taken in the same plane as Fig. 2.

Fig. 4 is a transverse sectional view of thefan wheel taken along the line IVIV of Fi 3.

iike numerals refer to similar parts in the several figures.

In the drawings the numeral 1 refers to a casing of the usual scroll type having parallel plain end walls 2 which are provided with concentric circular inlet orifices 3. The casing 1 is also provided with atangentially disposed outlet funnel 1. Suitably supported 1n alignment with the axis of the inlet orlfices 3 are the journal bearings 5 wherein is supported the shaft 6 perpendicular to the end Walls 2. To the shaft 6 is fixed a hub 7 having an extension flange 8, preferably positioned centrally of the casing, and to this flange 8 are fixed the fan blades 9. The fan blades 9 project at both sides of the flange 8, parallel with the shaft 6 and their outer ends are fixed to the annular end plates 10 by which the blades are braced together to form a rigid wheel.

The service for which this fan is especially designed calls for relatively high static air pressure in the discharge funnel 4. To produce such pressure the fan wheel normally revolves at relatively high speed, and to fur- 'faces of. the end walls 2 'of the casing.

.tact with the casing.

1927. Serial No. 204,803.

th er increase this static pressure in the discharge funnel, the end plates 10 are inclined inwardly, forming truncatedcones by which the outflowing current of air is concentrated near the medial plane of the casing. Due to this construction there is a relatively wide dead air space adjacent the walls 2 at each end of the casing, which, due to the great dif ference in pressure between the discharge funnel and the inlet orifices, tends to produce regurgitation of the air at the inlet orifices of the fan wheel. vTo overcomethis difficulty I have provided, at the inlet orifices of the "casing, the outwardly projecting conical flanges 11 which serve as funnels to guide the inflowingair. currents, -.These funnels are.

extended inwardly by the'cylindrieal flanges -12 which guide. the air currents to the fan wheel. Projecting outwardly from the inneredges of the end plateslO are cylindricah flanges 13 which extend outside of'and well beyond the inner ends of the flanges 1 2 and parallel thereto. To the flanges 13 are adjustably fixed, in any suitable manner as by 'the bolts 14 extending through axially extending slots therein, the sealing strips 15 of such width as to contact with the inner sur- The strips 15 thus formtubular gaskets andare composed of flexiblefabricmaterial of such a, character as to rub upon the inner surfaces of the end walls 2 without material friction, and to withstand the wear occasioned thereby. When the sealing strips become so worn as to break the sealbetween the fan wheel and the casing, the attachment bolts 14 may be loosened and the strips 15 adjusted to restore con- Theflexible fabric or equivalent material of elements: 15 constitutes an anti friction material as opposed tometallic material.

.By the construction above described the air in the, dead air spaces at the ends of the fan casing is efl'ectively sealed oil from the inlet orifices, thereby preventing regurgita- Q tion and greatly increasing the efficiency of the apparatus.

What I claim is: I

1. In a device of the class described, a casing element, a rotor element in the casing ele ment having a tubular axial inlet member, said casing having a side wall normal to the rotor axis and provided with an inlet opening coaxial with the rotor, a tubular gasket of anti-friction material surrounding said tubular inlet member and axially adjustable thereon to form a sealing contact with the casing side wall marginally of the latters inlet opening, and removable means securing the gasket to the tubular inlet member.

2. In a device of the class described, a casing element, a rotor element in the casing element having a tubular axial inlet member, said casing having a side wall normal to the rotor axis and provided with an inlet opening coaxial with the rotor, a tubular gasket of anti-fricti on material surrounding said tubular inlet member and axially adjustable thereon to form a sealing contact with the casing side wall marginally of the latters inlet opening and removable means securing the gasket to the tubular inlet member, said casing having an outlet opening through which said removable means is accessible.

3. In a device of the class described, a casing element, a rotor element in the casing element having a tubular axial inlet member,

said casing having a side wall normal to the rotor axis and provided with an inlet opening coaxial with the rotor, a tubular element fixed in said inlet opening and extendingwithin said inlet member, a tubular gasket of antifriction material surrounding said inlet member and axially adjustable thereon to form a sealing contact with the casing side wall marginally of the latters inlet opening, and removable means securing the gasket to said inlet member.

4. In a device of the classdescribed acasing element, a rotor element in the casing element having a tubular axial inlet member, said casing having a side wall normal to the rotor axis and provided with an inlet opening coaxial with the rotor, a tubular element fixed in said inlet opening and extending within said inlet member, a tubular gasket of anti-friction material surrounding said inlet member and axially adjustable thereon to form a sealing contact with the casing side wall marginally of the latters inlet opening, and removable means securing the gasket to said inlet member, said casing-having'an outlet opening through which said removable means is accessible.

In testimony whereof I have hereunto set my hand.

WILLIAM J. MONTGOMERY. 

